Abstract: When encountering the chaff centroid jamming (CSJ) during its tracking phase, anti-ship missile can’t adopt some recognition approaches to discriminate the target ship from jamming as they fall into the same resolution cell of terminal radar seeker. The application of oblique projection polarization filtering to the rejection of CSJ is discussed. The echoes of target and jamming in polarimetric radar seeker were modeled in the unresolved case, their amplitude probability density function (PDF) were analyzed to derive the angle measuring error PDF of the amplitude comparison monopulse system affected by CSJ, and statistical property of angle error was made. An oblique projection polarization filtering based anti-jamming approach was then introduced on the demonstration of oblique projection principles. Simulation was conducted in a representative scenario to validate the proposed anti-jamming approach, and its anti-jamming performance was also examined.